<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style>
			#container {
				width: 800px;
				height: 400px;
				margin: 10px auto;
				border: 1px solid black;
				overflow: hidden;
			}
			#buttons {
				width: 800px;
				margin: 10px auto;
				text-align: center;
			}
			#add, #fla {
				border: none;
				outline: none;
				width: 80px;
				height: 30px;
				background-color: red;
				color: white;
				font-size: 16px;
				cursor: pointer;
			}
			.small {
				width: 80px;
				height: 80px;
				float: left;
			}
		</style>
	</head>
	<body>
		<div id="container"></div>
		<div id="buttons">
			<button id="add">添加</button>
			<button id="fla">闪烁</button>
		</div>
		<script src="js/mylib.js"></script>
		<script>
			var bigDiv = document.querySelector('#container');
			var addButton = document.querySelector('#add');
			addButton.addEventListener('click', function() {
				var smallDiv = document.createElement('div');
				 smallDiv.className = 'small';
				// smallDiv.style.width = '80px';
				// smallDiv.style.height = '80px';
				// smallDiv.style.float = 'left';
				smallDiv.style.backgroundColor = randomColor();
				bigDiv.insertBefore(smallDiv, bigDiv.firstChild);
			});
			var flaButton = document.querySelector('#fla');
			var isFlashing = false;
			var timerId;
			flaButton.addEventListener('click', function(evt) {
				isFlashing = !isFlashing;
				if (isFlashing) {
					timerId = window.setInterval(function() {
						var divs = document.querySelectorAll('#container>div');
						for (var i = 0; i < divs.length; i += 1) {
							divs[i].style.backgroundColor = randomColor();
						}
					}, 200);
					flaButton.textContent = '暂停';
				} else {
					window.clearInterval(timerId);
					flaButton.textContent = '闪烁';
				}
			});
		</script>
	</body>
</html>
